In a GSM (Global System for Mobile Communications) network today, each registered mobile station has to monitor its own paging group on the paging channel. This procedure is performed periodically, with a monitoring cycle which is between 0.47 and 2.12 seconds, depending on the parameter BS-PA-MFRMS, as defined in 3GPP TS 44.018 chapter 10.5.2.11. The length of the cycle is set in order to obtain an acceptable responsiveness for mobile station call set-up procedures without consuming too much battery lifetime from the mobile station.
In existing paging solutions, a mobile station's monitoring of its paging channel is done with a view to communication that is time critical, i.e. communication that has to be initiated as soon as possible after a mobile station's initial reception of an incoming paging message. This process means that each mobile station has to spend a rather significant amount of energy decoding information not intended for that mobile station.